Atomizing oil burner



June 21, 1966 P. VOLKERT ATOMIZING OIL BURNER Filed Aug. 15, 1963 INVENT OR PETER YOLKER M Ma QM ATTORNEYS United States Patent 3,256,925 ATOMIZING OIL BURNER Peter Volkert, Neckarsulm, Germany, assignor to Firma Robert Volkert, Neckarsulm, Germany Filed Aug. 15, 1963, Ser. No. 302,368 7 Claims priority, application Germany, Sept. 26, 1962,

V 14,423; Feb. 21, 1963, V 23,677 4 Claims. (Cl. 15828) This invention relates to an atomizing oil burner in which the oil is atomized through a nozzle and sprayed into the combustion space. In atomizing oil burners of known type, the nozzle, to which the oil is supplied at a relatively high pressure, is fixed. Moreover, a blower is provided which produces an air stream enveloping concentrically the nozzle and introducing into the combustion space the air necessary for combustion. Said highpressure atomizing oil burners require a minimum oil pressure of approximately 7 atmospheres gauge if the oil is to be atomized satisfactorily for adequate combustion to take place. However, the oil flow through said burners is dependent on the oil pressure, and since the size of the nozzle opening cannot be reduced indefinitely for technical reasons, especially to avoid frequent clogging, these systems have been known to fail during times of low pressure. Therefore, there is a lower limit to the range of application of said known high-pressure atomizing oil burners.

On the other hand, a rotary oil burner is known in which the fuel oil is introduced without pressure into a motor-driven hollow shaft. At the front end of said 7 hollow shaft, a funnel is provided along whose inner spray of said nozzle being directed into the combustion space, and that the fuel oil is supplied under pressure to the nozzle through said shaft.

The particular advantage of the invention resides in p the fact that the spray produced by the nozzle also rotates about the shaft axis, and that in this manner, the oil droplets are mixed much better with the combustion air so that very eflicient combustion is obtained. Said burner can be employed with both very high and very low capacities. As a matter of fact, because of the rotary movement of the nozzle, the fuel oil need not be supplied to the nozzle at the empirically determined pressure of approximately 7 atmospheres gauge under any circumstances to obtain adequate atomization. Rather, the rotary movement of the nozzleenables the oil to be adequately atomized and mixed with the air of combustion even if it is supplied to the nozzle at much less than 7 atmospheres gauge pressure. -Therefore, the

' zles may alternatively be arranged concentrically around the shaft axis, when the fuel oil is supplied to said nozzles through ducts in the shaft.

The axis of the spray produced by a nozzle may exv blower wheel.

Patented June 21, 1966 tend parallel to the shaft axis. In other embodiments of the invention, however, the axis of the spray produced by the nozzle may alternatively be directed somewhat at an angle with the shaft axis so that owing to the rotary movement of the nozzle, a comparatively broad spray cone is obtained.

Generally, photocells or photo-conductive cells are employed to supervise such burners. Said light-sensitive cells are controlled by the light of the flame. However, such elements cannot be positioned at any desired point of the combustion space, since they must be protected from heat radiation and contamination. As in 'the burner according to the invention, the axis of the rotating shaft is directed towards the combustion space, the blower wheel can be arranged directly back of the nozzle, and the photocell may be mounted back of the Thus, the photocell is screened against the combustion space by the blower wheel. The light of the flame can reach the photocell through the blower wheel blades. Where this is not possible because of the construction of the blower or the guide vanes, the hub of the blower wheel is provided with apertures through which the light of the flame impinges on the photocell arranged back of the blower wheel.

In one embodiment of the invention, all parts of the burner are mounted on a bottom pan serving as a mounting :pla'te. This assembly-is covered up by an upper shell. Therefore, to repair or clean the burner it is only necessary to remove said upper shell to make all parts of the burner accessible. In burners of known type, the blower wheel had first to be removed from its shaft to provide access to the inner parts of the burner. In one embodiment of the invention, the housing may be split horizontally in the vicinity of its center plane. The lower section thereof may be in the form of a flat plate and the upper section, in the form of a hood covering said plate and the elements arranged thereon.

The speeds at which the oil pump, blower wheel and atomizer nozzle are caused to rotate may vary. In a preferred embodiment of the invention, the oil pump, blower wheel and rotating atomizer nozzle all are arranged in one axis, preferably onone and the same shaft. Thus, the oil pump is mounted on the same motor shaft, which also rotates the blower Wheel and the nozzle. Through a copper tube, the pump outlet communicates directly with the cavity provided in the shaft axis.

The leakage oil exuding from this sealing point flows directly to the pump sump or to another point on the pump, from which it is again taken up directly by the pump.

Other features of the invention will appear from the following description of an embodiment of the invention in connection with the drawing and appended claims and may be embodied in each form of construction of the invention either individually or in combination.

The drawing shows in plan view the burner of the invention, partly in section and with the housing upper section removed.

Fastened to a housing lower section or mounting plate 1 is a drive motor 2 of the hollow shaft type. Secured to the hollow shaft 3 driven by said motor 2 is a blower wheel 4. Secured to the front end face of the hollow shaft 3 is a nozzle 5. Fastened to the rear end of the hollow shaft 3 is an -oil pump, for example, a geared ump 6. The pressure oil outlet of the pump communicates through a copper tube 7 with the cavity extending along the axis of the hollow shaft 3. The sealing face 8, from which oil might leak at the connection between the copper tube 7 and the hollow shaft 3, has been removed to the interior of the pump so that any leakage oil is recovered instantly by the pump.

Arranged back of the blower wheel 4 is a photocell 9,

which is illuminated through holes 11 extending through a hub 10 of the blower wheel 4. Arranged in front of the blower wheel 4 are air guide vanes 12 and ignition electrodes 13. The blower air is drawn in from the rear past an adjustable iris diaphragm 14 enabling the air throughput to be adjusted. Directly in front of the nozzle 5, a chamber 15 is provided about whose aXis a smaller aperture 16 and a larger aperture 17 are provided. The boiler furnace is located adpacent to the chamber 15. Also arranged on the housing section 1 are a control unit 18 and an ignition transformer 19. The housing section 1 is covered by a hood or shell.

What I claim is:

1. An oil burner in which oil is atomized by a nozzle and sprayed into a combustion space comprising acombustion space, a hollow shaft having one end facing said combustion space, at least one atomizer nozzle provided on the end of said hollow shaft facing said combustion space, means for rotating said shaft, means for supplying fuel oil to said nozzle under pressure through said shaft so that the spray from said nozzle is directed into said combustion space, a blower wheel attached to said shaft so as to blow air past said nozzle into said combustion space and photo-cell means arranged on the opposite side of said blower from said nozzle and in a position to receive radiation from the combustion space for controlling said burner, said blower Wheel having a hub portion containing a plurality of apertures in substantial alignment with said photo-cell means so as to permit radiation from said combustion space to enter said photo-cell means.

2. An oil burner as defined in claim 1 in which all of the parts of said burner exclusive of the combustion space are arranged on a lower housing section which serves as a mounting plate.

3. An oil burner in which oil is atomized by a nozzle and sprayed into a combustion space comprising a combustion space, a hollow shaft having one end facing said combustion space, at least one atomizer nozzle provided on the end of said hollow shaft facing said combustion space, means for rotating said shaft, means for supplying fuel oil to said nozzle under pressure through said shaft so that the spray from said nozzle is directed into said combustion space, a blower wheel attached to said shaft so as to blow air past said nozzle into said combustion space and photo-cell means arranged on the opposite side of said blower wheel from said nozzle and in a position to receive radiation from the combustion space for controlling said burner, said blower wheel having a hub portion containing a plurality of apertures in substantial alignment with said photo-cell means so as to permit radiation from said combustion space to enter said photocell means, an iris diaphragm positioned about said lower wheel hub portion between said blower wheel and said photo-cell means for regulating the amount of air supplied to said blower wheel.

4. An oil burner as defined in claim 1, wherein said means for supplying fuel oil to said nozzle under pressure is an oil pump which is operatively associated in a driven manner with the end of said shaft furthest from said combustion space and said furthest end of said shaft is connected by means of a conduit to the pressure oil outlet of said pump.

References Cited by the Examiner UNITED STATES PATENTS 2,226,212 12/1940 Wood 15877 FOREIGN PATENTS 148,767 3/ 1936 Austria. 634,072 1/ 1962 Canada. 1,128,417 8/1956 France.

FREDERICK L. MATIESON, JR., Primary Examiner.

MEYER PERLIN, JAMES W. WESTHAVER, S. W.

MILLARD, Examiners. 

1. AN OIL BURNER IN WHICH OIL IS ATOMIZED BY A NOZZLE AND SPRAYED INTO A COMBUSTION SPACE COMPRISING A COMBUSTION SPACE, A HOLLOW SHAFT HAVING ONE END FACING SAID COMBUSTION SPACE, AT LEAST ONE ATOMIZER NOZZLE PROVIDED ON THE END OF SAID HOLLOW SHAFT FACING SAID COMBUSTION SPACE, MEANS FOR ROTATING SAID SHAFT, MEANS FOR SUPPLYING FUEL OIL TO SAID NOZZLE UNDER PRESSURE THROUGH SAID SHAFT SO THAT THE SPRAY FROM SAID NOZZLE IS DIRECTED INTO SAID COMBUSTION SPACE, A BLOWER WHEEL ATTACHED TO SAID SHAFT SO AS TO BLOW AIR PAST SAID NOZZLE INTO SAID COMBUSTION SPACE AND PHOTO-CELL MEANS ARRANGED ON THE OPPOSITE SIDE OF SAID BLOWER FROM SAID NOZZLE AND IN A POSITION TO RECEIVE RADIATION FROM THE COMBUSTION SPACE FOR CONTROLLING SAID BURNER, SAID BLOWER WHEEL HAVING A HUB PORTION CONTAINING A PLURALITY OF APERTURES IN SUBSTANTIAL ALIGNMENT WITH SAID PHOTO-CELL MEANS SO AS TO PERMIT RADIATION FROM SAID COMBUSTION SPACE TO ENTER SAID PHOTO-CELL MEANS. 